Balcony Solar

[NikLiverpool]

I started reading from the beginning of the topic and I must admit I am more confused now.
For example the chance of feeding back to the grid in case of a power cut. I am pretty sure that the ecoflow kits need live wires or they switch off.
Or in my case with the piwerwall if there is a power cut my home becomes an island and in theory it should happily carry on generating.
As I said before I need to dig further into this...

 

[Bam Bam]

Ok. Aware of this, been following this thread, have solar and maxed against what our maximum inverter limit is in NI (3.68kw) so could else be away around that limit?

You'd have to check the rules when they are released. But will NI have different regulations anyway?

At present my understanding is that you are supposed to inform your DNO if you have an inverter connected.

 

[Bam Bam]

I started reading from the beginning of the topic and I must admit I am more confused now.
For example the chance of feeding back to the grid in case of a power cut. I am pretty sure that the ecoflow kits need live wires or they switch off.
Or in my case with the piwerwall if there is a power cut my home becomes an island and in theory it should happily carry on generating.
As I said before I need to dig further into this...

From what I understand there are two broad concerns, but perhaps there are others I have missed...

There is a the potential backfeed issue (devices don't shut down when the grid goes down like they are supposed to). Hopefully the technology will stop this, if all the devices are of suitable quality and they don't get fooled into assuming that the grid remains when it is not. This is a risk to line workers.

Then there are the concerns about the internal wiring in people's homes not being capable of handling the extra load and overheating, which is a risk to those in the home.

Anything I've missed?

 

[Giller]

You'd have to check the rules when they are released. But will NI have different regulations anyway?

At present my understanding is that you are supposed to inform your DNO if you have an inverter connected.

Hmmm. I’m not jumping in on theses, in NI with our grid you can’t have more than a 3.68 inverter because of the infrastructure, I’ll see what happens.

 

[poldark]

Not perhaps relevant but I'll share it as it is fact, not conjecture.

I have a three bedroom house in Brittany, I paid €899 last year for a 1960W (4x490W) plug and play solar kit, fully compliant to French law.

Two are mounted vertically, in lieu of a fence for a portion of a patio roughly Westerly for the afternoon sun. The other two are ground-mounted on simple aluminium frames, angled so one is aligned ideally for the early part of the day and one for midday.

The grid tie inverter is connected to a socket on a dedicated circuit fortuitously within 3 metres via a cellar window.

The issue of the simple systems is a lot of generation is "lost" without batteries to support, which is what is now being heavily promoted with bidirectional AC coupled batteries.

Anyway, as I was asked recently by a friend if they were doing well I had a check of the data. I was very surprised to find that if I had been able to store and self consume all the generated output (admittedly ignoring conversion losses) just these four panels would have covered 93% of my modest consumption between April - Sept (admittedly the prime six months of the year).

Their current alignment is to provide base load cover for the greatest period, so when I buy supporting batteries in the next couple of months ( likely the new Jackery SolarVolt3 at circa €1500) they can be adapted and maybe output slightly more.

I believe around 400k of this sort of kit are now in use in France. The added bonus of the new batteries is they have AC outlet(s) that can provide back up supply to 2400W in the case of an outage.

 

[T1 Terry]

Not perhaps relevant but I'll share it as it is fact, not conjecture.

I have a three bedroom house in Brittany, I paid €899 last year for a 1960W (4x490W) plug and play solar kit, fully compliant to French law.

Two are mounted vertically, in lieu of a fence for a portion of a patio roughly Westerly for the afternoon sun. The other two are ground-mounted on simple aluminium frames, angled so one is aligned ideally for the early part of the day and one for midday.

The grid tie inverter is connected to a socket on a dedicated circuit fortuitously within 3 metres via a cellar window.

The issue of the simple systems is a lot of generation is "lost" without batteries to support, which is what is now being heavily promoted with bidirectional AC coupled batteries.

Anyway, as I was asked recently by a friend if they were doing well I had a check of the data. I was very surprised to find that if I had been able to store and self consume all the generated output (admittedly ignoring conversion losses) just these four panels would have covered 93% of my modest consumption between April - Sept (admittedly the prime six months of the year).

Their current alignment is to provide base load cover for the greatest period, so when I buy supporting batteries in the next couple of months ( likely the new Jackery SolarVolt3 at circa €1500) they can be adapted and maybe output slightly more.

I believe around 400k of these sort of kits are now in use in France. The added bonus of the new batteries is they have AC outlet(s) that can provide back up supply to 2400W in the case of an outage.

On a dedicated circuit, with battery back up and islanding to avoid pushing out to the grid in times of a grid outage, sounds like a great idea ... might be difficult for a renter to implement though, but certainly something that could be developed ....

T1 Terry

 

[GaryMG4]

Not perhaps relevant but I'll share it as it is fact, not conjecture.

I have a three bedroom house in Brittany, I paid €899 last year for a 1960W (4x490W) plug and play solar kit, fully compliant to French law.

Two are mounted vertically, in lieu of a fence for a portion of a patio roughly Westerly for the afternoon sun. The other two are ground-mounted on simple aluminium frames, angled so one is aligned ideally for the early part of the day and one for midday.

The grid tie inverter is connected to a socket on a dedicated circuit fortuitously within 3 metres via a cellar window.

The issue of the simple systems is a lot of generation is "lost" without batteries to support, which is what is now being heavily promoted with bidirectional AC coupled batteries.

Anyway, as I was asked recently by a friend if they were doing well I had a check of the data. I was very surprised to find that if I had been able to store and self consume all the generated output (admittedly ignoring conversion losses) just these four panels would have covered 93% of my modest consumption between April - Sept (admittedly the prime six months of the year).

Their current alignment is to provide base load cover for the greatest period, so when I buy supporting batteries in the next couple of months ( likely the new Jackery SolarVolt3 at circa €1500) they can be adapted and maybe output slightly more.

I believe around 400k of this sort of kit are now in use in France. The added bonus of the new batteries is they have AC outlet(s) that can provide back up supply to 2400W in the case of an outage.

A couple of things to consider (based on the ECoFlow Stream). The battery/inverter combination when grid tied will output 800W max so anything higher rated will also draw from th grid. In the case of the EcoFlow you can program it to discharge the battery at certain rate during certain hours, but it will just discharge that even if there is no load. You need to add a CT clamp and tell the battery to not discharge to the grid, that way the relatively small battery will cover your base load for longer.

 

[poldark]

The first generation units used the German legal limit of 800W but most of the new generation launched in the past three months offer optional 800 or 2400 (i.e. Marstek, Jackery, Zendure, Indevolt, Izypower)

Clearly there's a 10A cut-off upper limit, but not sure who's decided this. These units are all available to buy in France, Germany, Belgium & Austria.

Also Renters are exactly who these units are aimed at, plug and play with no permanent installation is the core design ethos - just so they can be moved easily to new properties.

 

[Everest]

I started reading from the beginning of the topic and I must admit I am more confused now.
For example the chance of feeding back to the grid in case of a power cut. I am pretty sure that the ecoflow kits need live wires or they switch off.

Zero. The inverters will cut out when grid power is lost. If that didn't happen users would be electrocuted from the live plug.

Or in my case with the piwerwall if there is a power cut my home becomes an island and in theory it should happily carry on generating.
As I said before I need to dig further into this...

That's a very good question. The PW3 is great for backup capability out-of-the box. However, IMHO, you should never connect a generating supply to an inverter's backup output.

Inverters will constantly attempt to push the phase by injecting a small frequency shift to the supply to detect if they are still connected to the utility grid. As that is not possible to increase the frequency of the national grid, they know they are still connected. If connected to a locally generated back-up source they may or may not be able to adjust the frequency. If they can't adjust the frequency of the Powerwall, they may be tricked into believing there is a local grid island.

BUT... grid-tied inverters are designed to run wide open at all times - without any control, or somewhere to send the power (the grid, usually - possibly the batteries in the PW until they are near full), they would just damage anything connected to it. Once the grid-tied inverter pushes current to a limited source that cannot take it the really bad day begins

My advice would be not to connect a plug-in solar system to the AC backup side of the Powerwall, unless you have clear technical confirmation that is possible from the supplier.

Same applies to the AC backup port of any hybrid inverter.

At present my understanding is that you are supposed to inform your DNO if you have an inverter connected.

Correct, but I suspect the 'plug-in solar' systems will be exempt from that. I'm sure the average Jo Blogs isn't going to chuck a new system into their basket in Lidl, come home, plug it in and then say to their partner... "right, I'm going to inform our DNO now, dear".

From what I understand there are two broad concerns, but perhaps there are others I have missed...

There is a the potential backfeed issue (devices don't shut down when the grid goes down like they are supposed to). Hopefully the technology will stop this, if all the devices are of suitable quality and they don't get fooled into assuming that the grid remains when it is not. This is a risk to line workers.

Yes: a) they will detect loss off grid by constant attempts to frequency shift and monitor for a stable grid.
b) micro-inverters will follow voltage, but not initiate it - they will only generate output current by raising voltage above the existing grid voltage.

Then there are the concerns about the internal wiring in people's homes not being capable of handling the extra load and overheating, which is a risk to those in the home.

Anything I've missed?

My main concern is having the supply on the load side of the existing RCD. You are relying on the plug-in-solar to disconnect sub 50mS to not have a lethal shock as the supply is not passing through the house's main RCD (or ring's RCBO).

Clearly there's a 10A cut-off upper limit, but not sure who's decided this. These units are all available to buy in France, Germany, Belgium & Austria.

Those countries have radial, rather than ring finals, so such limits would not be applicable to the UK.